Colorado State University

About: Colorado State University is a education organization based out in Fort Collins, Colorado, United States. It is known for research contribution in the topics: Population & Laser. The organization has 31430 authors who have published 69040 publications receiving 2724463 citations. The organization is also known as: CSU & Colorado Agricultural College.

GW190521: A Binary Black Hole Merger with a Total Mass of 150 M

Abstract: On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21} M_{⊙} and 66_{-18}^{+17} M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65 M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28} M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4} Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30} Gpc^{-3} yr^{-1}.

QIIME 2: Reproducible, interactive, scalable, and extensible microbiome data science

Abstract: We present QIIME 2, an open-source microbiome data science platform accessible to users spanning the microbiome research ecosystem, from scientists and engineers to clinicians and policy makers. QIIME 2 provides new features that will drive the next generation of microbiome research. These include interactive spatial and temporal analysis and visualization tools, support for metabolomics and shotgun metagenomics analysis, and automated data provenance tracking to ensure reproducible, transparent microbiome data science.

Cloud Feedbacks in the Climate System: A Critical Review

Abstract: This paper offers a critical review of the topic of cloud–climate feedbacks and exposes some of the underlying reasons for the inherent lack of understanding of these feedbacks and why progress might be expected on this important climate problem in the coming decade. Although many processes and related parameters come under the influence of clouds, it is argued that atmospheric processes fundamentally govern the cloud feedbacks via the relationship between the atmospheric circulations, cloudiness, and the radiative and latent heating of the atmosphere. It is also shown how perturbations to the atmospheric radiation budget that are induced by cloud changes in response to climate forcing dictate the eventual response of the global-mean hydrological cycle of the climate model to climate forcing. This suggests that cloud feedbacks are likely to control the bulk precipitation efficiency and associated responses of the planet’s hydrological cycle to climate radiative forcings. The paper provides a brie...

Texture, climate, and cultivation effects on soil organic matter content in U.S. grassland soils

Abstract: Soil organic C content, a major source of system stability in agroecosystems, is controlled by many factors that have complex interactions. The purpose of this study was to evaluate the major controls over soil organic carbon content, and to predict regional patterns of carbon in range and cultivated soils. We obtained pedon and climate data for 500 rangeland and 300 cultivated soils in the U.S. Central Plains Grasslands, and statistically analyzed relationships between C and soil texture and climate. Regression models of the regional soils database indicated that organic C increased with precipitation and clay content, and decreased with temperature. Analysis of cultivated and rangeland soils indicated that C losses due to cultivation increased with precipitation, and that relative organic C losses are lowest in clay soils. Application of the regression models to a regional climate database showed potential soil organic matter losses to be highest in the northeastern section of the Central Plains Grasslands, decreasing generally from east to west. These statistical data analyses can be combined with more mechanistic models to evaluate controls of soil organic matter formation and turnover, and the implications for regional management. S ORGANIC MATTER is a major component of biogeochemical cycles of the major nutrient elements, and the quantity and quality of soil organic matter both reflect and control primary productivity. The amount of soil organic matter represents the balance of primary productivity and decomposition and as such is a sensitive and integrated measure of change in ecosystem function. Understanding the processes that control soil organic matter dynamics and their I.C. Burke, CM. Yonker, W.J. Parton, C.V. Cole and D.S. Schimel, Natural Resource Ecology Lab., Colorado State Univ., Fort Collins, CO 80523; and K. Flach, Agronomy Dep., Colorado State Univ., Fort Collins, CO 80523. Received 20 June 1988. 'Corresponding author. Published in Soil Sci. Soc. Am. J. 53:800-805 (1989). response to management is essential for informed use of agricultural land. Jenny (1980) describes four sets of state factors responsible for the formation of soil organic matter, and illustrates the influence of parent material, time, climate, and biota as individual controls over soil properties. Controls over soil organic matter properties may have complex interactions; separate analysis of such controls may limit useful predictions. Parton et al. (1988) illustrate the use of a mechanistic model in evaluating simultaneously changing controls. Although such models can be highly successful, field data are necessary to validate predictions across complex gradients. It is widely recognized that cultivation of grassland soils leads to depletion of soil organic matter (Alway, 1909; Russel, 1929; Hide and Metzger, 1939; Haas et al., 1957; and many others). Soil organic C losses of as much as 50% have been documented in the U.S. Central Plains Grasslands (Haas et al., 1957), with losses strongly dependent on management regime and regional location. The extent of soil organic matter depletion has been shown to depend upon the same variables as those controlling soil organic matter formation: climate (Haas et al., 1957; Honeycutt, 1986; Cole et al., 1989), soil texture (Tiessen et al., 1982; Schimel et al., 1985a), landscape position (Schimel et al., 1985a,b; Honeycutt, 1986; Yonker et al., 1988), and management regime (Janzen, 1987; Cole et al., 1988). An integrated assessment of soil organic matter losses across the U.S. Central Grasslands requires analysis of soils with varying temperature, precipitation, and soil physical properties. The objectives of this paper were threefold: (i) to establish quantitative relationships between native soil organic matter levels in the Central Plains Grasslands and key driving variables: precipitation, temperature, and soil texture; (ii) to develop predictions of cultivation induced soil organic carbon loss as a function BURKE ET AL.: TEXTURE, CLIMATE, AND CULTIVATION EFFECTS ON U.S. GRASSLAND SOILS 801 of climate and soil texture; and (iii) to use these predictions to map potential soil organic C depletion.

Regional climate impacts of the Northern Hemisphere annular mode

Abstract: The Northern Hemisphere annular mode (NAM) (also known as the North Atlantic Oscillation) is shown to exert a strong influence on wintertime climate, not only over the Euro-Atlantic half of the hemisphere as documented in previous studies, but over the Pacific half as well. It affects not only the mean conditions, but also the day-to-day variability, modulating the intensity of mid-latitude storms and the frequency of occurrence of high-latitude blocking and cold air outbreaks throughout the hemisphere. The recent trend in the NAM toward its high-index polarity with stronger subpolar westerlies has tended to reduce the severity of winter weather over most middle- and high-latitude Northern Hemisphere continental regions.